Collagenase, the enzyme which cleaves collagens, is widely distributed in organisms.
Since an elevated collagenase activity is noted in pathological tissues such as synovialis in rheumatoid arthritis, ulcerated cornea and osteoma tissues, it is beneficial to determine collagenase activity in pathological tissues and in body fluids for diagnosis of such disorders.
Collagenase is produced in a latent (inactive) form, procollagenase, and both of collagenase and procollagenase occur in tissues. Therefore, for the assay of collagenase activity, procollagenase has to be activated by a pretreatment with a protease such as trypsin or with a mercurial compound, etc. Moreover, as a large quantity of inhibitors of collagenase activity is present in tissues, a very complicated procedure is required in order to eliminate these inhibitors.
Several types of collagenases are known according to the types of their collagen substrates, and they are classified into the collagenase that cleaves type I, type II and type III collagens (interstitial collagens) (hereinafter referred to as interstitial collagenase), the collagenase that cleaves type IV collagen and type V collagen, and the like.
With regard to the monoclonal antibodies against the procollagenase of the interstitial collagenase (hereinafter referred to as "interstitial procollagenase"), 11 monoclonal antibodies have been disclosed, which were prepared by using as antigens a mixture of the interstitial procollagenases having a molecular weight of 52000 and 57000 [see Biochemistry, 27, 6751 (1988)]. However, the monoclonal antibodies of the present invention, which belong to the immunoglobulin in class and subclass G.sub.1, whose L-chain isotype is kappa and which have a collagenase inhibiting activity, have never been disclosed before.